Metabolism of progesterone in rat uterus

Saffran, Judith; Loeser, Bonnie K.; Haas, Bernadette; Stavely, Homer E.

doi:10.1016/0039-128x(74)90145-7

Cited by 23 publications

(3 citation statements)

References 26 publications

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“…Progesterone metabolism by the mouse uterus is not unexpected, since there are several earlier reports showing that mammalian endometrial tissue can metabolize P 4 (25, 26, 29±31). The influence of the E 2 metabolism of P 4 by this tissue is primarily directed towards the formation of some inactive metabolites (24). In the present study, very small amounts of inactive metabolites of P 4 , namely 3a-OH-5b-pregnan-20-one and 5b-3a-17a,20b-P, have been identified in both LH-stimulated and -unstimulated uterine tissues.…”

mentioning

confidence: 67%

Stimulation of pregnenolone metabolism and aromatase activity by luteinizing hormone in mouse uterus

Debnath

Mukherjee²,

Bhattachryya³

2000

European Journal of Endocrinology

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In vitro metabolism of pregnenolone (P 5 ) as well as production of 17b-estradiol (E 2 ) were studied in uteri of untreated and luteinizing hormone (LH)-treated mice that had been ovariectomized (OVX) at late-diestrus stage. In the uteri of untreated mice, [ 3 H]pregnenolone was shown to be metabolized to D 5-components such as 17a-hydroxypregnenolone (17a-P 5 ) and dehydroepiandrosterone (DHEA), whereas LH treatment resulted in significant increases in the formation of progesterone (P 4 ), 17a-hydroxyprogesterone (17a-P 4 ), androstenedione (AD) and testosterone (T). This was assessed by thinlayer chromatography (TLC) and high-performance liquid chromatography (HPLC). The content and release of P 4 was shown to be stimulated by LH. Trilostane, an inhibitor of 3b-hydroxysteroid dehydrogenase (3b-HSD), inhibited LH-induced P 4 synthesis and its release in a dose-dependent manner. A considerable increase in [ -3-oxosteroids. In vitro effects of LH on the synthesis and metabolism of P 4 , as well as on the stimulation of aromatase activity, were more pronounced in the uterine tissue of LH-primed OVX mice. Thus the results of the present study indicate that, under specific conditions, the uterus of the mouse behaves like steroidogenic tissue. Its prompt response to LH reveals the probable physiological relevance of the existence of LH receptors of high binding affinity in the uterine tissue of the mouse, as reported earlier.

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confidence: 67%

Stimulation of pregnenolone metabolism and aromatase activity by luteinizing hormone in mouse uterus

Debnath

Mukherjee²,

Bhattachryya³

2000

European Journal of Endocrinology

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“…Saffron et al (1974) proposed that oestrogen treatment increases ring A reducíase activity in the rat uterus, but that at low progesterone concentration, less ring A metabolism occurs because the progesterone is protected by its binding to receptor proteins which are also increased by oestrogen treatment. My results do not support this proposal since the oestrogen effect was not influenced by the dose of progesterone (P<Q-0S).…”

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confidence: 98%

“…However, the pattern of metabolites produced is dependent on the concentration of progesterone used in vitro (Saffron, Loeser, Haas & Stavely, 1974). When high concentrations of progesterone were used, oestrogen increased both ring A and C20-ketone metabolism.…”

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confidence: 99%

Effect of Oestrogen Priming on the Pattern of Progesterone Metabolism in the Mouse Uterus

Clark¹

1975

Journal of Endocrinology

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Oestrogen treatment in vivo increases the metabolism of progesterone by the rat uterus in vitro (Armstrong & King, 1971;Howard & Wiest, 1972). However, the pattern of metabolites produced is dependent on the concentration of progesterone used in vitro (Saffron, Loeser, Haas & Stavely, 1974). When high concentrations of progesterone were used, oestrogen increased both ring A and C20-ketone metabolism. At low concentrations oestrogen increased C20-ketone metabolism, whereas ring A metabolism was decreased.This present experiment was carried out to see whether oestrogen affected uterine meta¬ bolism of progesterone in vivo in mice (Clark, 1973(Clark, , 1974 in the same way.[1,2,6,7-3H] Progesterone (5 or SOOpg; sp. act. 261 µ ^, Radiochemical Centie, Amersham) was injected intraluminally into both uterine horns of spayed mice 1 or 6 days after oestrogen priming as described by Clark (1973). Five picograms of progesterone may be bound in the uterus but 500 pg would exceed the binding capacity of the uterus (Clark, 1973(Clark, , 1974. On day 6, responsiveness of the uterus to progesterone and oestrogen is qualitatively the same as that of the untreated ovariectomized mouse but the uteri are larger and their responses less variable.Groups of 5 uteri were removed 5 min after injection and immediately extracted three times with 5 ml chloroform:methanol (2:1, v/v). The pooled solvent was evaporated to dryness at 70°C under nitrogen. The residue was dissolved in 10 ml aqueous 70% methanol and stored overnight at -20°C. After centrifugation at 800 g for 10min at 4°C the supernatant was removed and evaporated to dryness. The residue was partitioned between water and ethyl acetate (5 : 10, v/v). The ethyl acetate was removed and an aliquot taken for estimation of total radioactivity. After addition of 50 µg each of unlabelled reference steroids corresponding to compounds previously found in the mouse uterus (5a-pregnane-3a,20a-diol; 20a-hydroxypregn-4-en-3-one; 3a-hydroxy-5a-pregnan-20-one; 5a-pregnane-3,20-dione and progesterone), the progesterone metabolites were separated by thin-layer chromatography (Armstrong & King, 1971). This method separates the above compounds into six discrete spots which were located by exposure to iodine vapour. In this experiment, as previously found by Clark (1974), negligible radioactivity was found in areas outside the spots. Recrystallization to constant specific activity had previously demonstrated that, for mouse uterine metabolism of pro¬ gesterone, radioactivity in each spot is indeed associated with the particular reference com¬ pound (Clark, 1974). Silica gel from reference spots or from intervening areas was sucked into cotton-wool plugged Pasteur pipettes and eluted with 2 2 ml chloroform : methanol (2:1, v/v) into counting vials. Samples were dried overnight: 5 ml toluene containing 0-3 % PPO and 0-1 % POPOP were added to each vial and the radioactivity was counted by liquid scintillation spectrometry. Figure 1 shows that metabolism of progesterone was greatest immediately after oes...

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Hormonal Modulation of Progesterone Receptors

Saffran

Loeser

1981

Reproductive Processes and Contraception

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Metabolism of progesterone in rat uterus

Cited by 23 publications

References 26 publications

Stimulation of pregnenolone metabolism and aromatase activity by luteinizing hormone in mouse uterus

Stimulation of pregnenolone metabolism and aromatase activity by luteinizing hormone in mouse uterus

Effect of Oestrogen Priming on the Pattern of Progesterone Metabolism in the Mouse Uterus

Hormonal Modulation of Progesterone Receptors

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